1. Field of Invention
The present invention relates generally to a structure of pattern pressing roller suitable for pressed printing on the cardboards. More particularly, the present invention relates to a structure of pattern pressing roller that can provide various patterns or diagrams on the cardboards through the pressed printing process.
2. Description of the Related Art
The patterns on the cardboard are pressed-printed by the pattern pressing roller comprising the corresponding pattern on its surface. In other words, the patterns on the cardboards will be various according to the carved patterns on the surfaces of the rollers.
The conventional fabrication of the patterns on the cardboard usually provides some straight lines or wave line patterns. Since the cardboards cannot generally subject to the compressing pressure process, therefore, the thickness on the cardboards is increased in order to improve its hardness so that it can provide some resistance toward the pressing pressure.
The hardness of the cardboards is the main problem that is well known in the prior art, a lot people in this field have tried to find different ways to resolve the problem. In recent years, the hardness of the cardboards is gradually improved. It is an object of the invention to provide a pattern pressing roller that can improve the hardness of the cardboards based on inventive ideas of the inventor, his years of experiences in this field. In order to pressed print a desired pattern onto the cardboards, the pattern pressing roller must consists the desired pattern. The pattern is normally carved through the carving equipment to sculpt onto the surface areas of the roller in order to produce the desired pattern onto the surface of the roller. However, a lot of these patterns are complex with highly density of patterns or drawings that the accuracy of producing those complex patterns is very difficult. Particularly, a weariness problem is normally occurred during the carving process. Further, if those conventional carving equipments of the pattern pressing roller have not been through a heat process to increase its hardness in the first place, then once the patterns are completed on the roller and those pattern pressing roller goes through a heat process, the patterns or the size of the patterns on the roller will be distorted due to the heat. To repairing or re-sculpt those distorted patterns becomes very difficult, the cost and time are consuming. Thus, the efficiency of the fabrication is reduced.
During the pressing process, those patterns on the surfaces of the pattern pressing rollers will eventually wear out due to the surface friction. But the conventional pattern pressing rollers are difficult and costly to repair or re-carve its patterns on the surface of the rollers. Unless the patterns are very badly to be seen or distorted badly, otherwise it is not wise to increase the production cost by repairing or replacing the damaged rollers frequently. It is understandable that in such condition, the pressing quality is not very good due to the cost and inconvenience. Further, the repairing process is lengthy and inconvenient, so it induces another problem in the production process.